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Optimizing multi-parameter distributed fiber sensors:a hybrid Rayleigh-Brillouin-Raman System approach

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Light(Science & Applications) 2024年第3期13卷 393-395页

作者： Kwang Yong Song dept.of Physics Chung-Ang University84 Heukseok-roDongjak-guSeoul 06974Korea

An optimized single-end hybrid Rayleigh,Brillouin,and Raman distributed fiber sensing system has been developed for simultaneous measurement of multiple parameters.This system integrates 3-bit pulse coding for the Raman signal and the Brillouin amplification of the Rayleigh-backscattered signal,discriminating strain,temperature,and vibration using a single sensing fiber.

关键词： fiber Rayleigh signal

An integrated spatial planning of the mountainous landscapes for ski sports in a case area at the eastern Türkiye

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Journal of Mountain Science 2024年第3期21卷 754-767页

作者： SATIR Onur TOSUN Busra COSKUN OZYOL Funda OZDEMIR Omer Faruk BERBEROGLU Suha dept.of Landscape Architecture Van Yuzuncu Yil UniversityVan 65090Türkiye School of Physical Education&Sports Van Yuzuncu Yil UniversityVan 65090Türkiye Van Yuzuncu Yil University dept.of Architecture&Urban Planning Van 65090Türkiye dept.of Remote Sensing&GIS Cukurova UniversityAdana 01330Türkiye

Mountainous regions have disadvantages in economic development because of harsh physical and climatic conditions.However,winter tourism activities are one of the key components for supporting economic development in the highlands.Establishing a ski resort area supports direct and indirect employment in a region,and it stops immigration from mountainous regions to other places.This research aimed to assess the potential ski areas using a multi criteria evaluation technique in the Van region which is located in the eastern part of Türkiye.In this context,snow cover duration,sun effect,slope,slope length,elevation,population density,distance from main roads and lake visibility were used as input factors in the decision making process.Each factor was standardized using a fuzzy technique based on existing well-known ski centers in Türkiye.The weight of inputs was defined by applying a survey to the professional skiers.The most important factors were detected as transportation opportunities and snow covers whereas,the least important factors were elevation and population density.Additionally,lake visibility was very important to make a difference from other existing facilities in the region.Therefore,it was included as constraints and lake visible areas were extracted at the final stage of the research.Potential ski areas were mapped in three levels as professional,intermediate and beginner skiers.One of the suitable areas was selected as a sample projection and for the 3D simulation of the ski investment area.Potential costs and benefits were discussed.It was found that a ski tourism area investment can be amortized in 3 years in the region.

关键词： Winter sports and tourism Decision making 3D simulation and modelling Landscape planning GIS

Challenges facing the USA in matching Germany on advanced manufacturing for green growth

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International Journal of Innovation Studies 2024年第1期8卷 13-24页

作者： Mikael Skou Andersen Aarhus University Dept.of Environmental ScienceKatrinebjergvej 89G8200Aarhus N.Denmark

This study explores the relative strength of public policies promoting advanced manufacturing by comparing the government programs and capacities of two world leaders in science and technology:the USA and Germany.Based on insights from’varieties-of-capitalism’literature and using process tracing methodology,this study identifies significant differences in today’s pursuit of advanced manufacturing.The German model of Rhine capitalism has strength due to its long tradition of diversified quality work,built on a long-term commitment to government-industry collaboration,with significant indirect public support provided by vocational training and research institutes.The American model of Manchester capitalism has been challenged by the loss of millions of low-skilled manufacturing jobs due to outsourcing and competition from Asia.The study finds that the“Manufacturing USA”policy initiative of the Obama era,although directly inspired by Germany’s Fraunhofer institutes,is hampered by the contextual and institutional circumstances identified.With biobased carbon fibers offering the potential of a novel,low-cost material,pursued with research and development(R&D)efforts in both countries,it provides a measure for evaluating policy outcomes,and the study confirms Germany’s technological lead.In addition,the study’s process-tracing methodology reveals that significant legacies from German knowledge creation in the past have spilled over to American science and technology,and may continue to do so,lured by government funds.Further studies on advanced manufacturing should test the robustness of these findings.

关键词： Research policy Industry 4.0 Bioeconomy Low-carbon innovation Varieties of capitalism Process tracing

A Multi-Channel CMOS Analog Front-End Interface IC with 157.8 d B Current Detection Dynamic Range

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Chinese Journal of Electronics 2024年第2期33卷 393-402页

作者： Kunyu WANG Wenjing XU Chengbin ZHANG Yanjun YANG Man-Kay LAW Li ZHOU Jie CHEN Ming CHEN Institute of Microelectronics of the Chinese Academy of Science University of Chinese Academy of Sciences Zunyi Normal University Institute of Microelectronics and dept.of ECE FST University of Macau

A high dynamic range and low-noise CMOS(complementary metal-oxide-semiconductor transistor)front-end interface integrated circuit(IC) with multi-channel detection is presented in this paper. Two different current detection channels, composed of a trans-impedance amplifier(TIA) and an integrator-differentiator TIA, are used to boost the current detection range. A capacitance-coupled instrument amplifier(CCIA) is also included to realize high precision voltage detection. A fourth-order sigma-delta modulator using a second-order loop filter and a second-order noise shaping integral quantizer is adopted to realize effective number of bits above 16 bits. The presented interface IC is implemented in 0.18-μm CMOS process with supply voltage of 3.3 V, and a proto-type electrochemical sensor platform with miniaturized sensor array is developed to verify the functionality of the interface IC. Measurement results indicate that the designed interface IC achieves 157.8 d B current detection dynamic range, and the measured input-referred current noise and voltage noise floor are 1.04 p A and 58.4 n V within 10 k Hz integration bandwidths,respectively.

关键词： Readout integrated circuit Sigma-delta modulator Complementary metal-oxide-semiconductor transistor Current detection dynamic range

A Warm Reception for the Year of the Dragon

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国际人才交流 2024年第3期 61-62页

作者： Michael John Harrold Documentary dept CGTN

A dragon year,so I read somewhere,is one in which,individually and collectively,we are filled with energy and confidence.It’s supposed to be a year of transformation,good fortune and prosperity;all of which,it seems ... 详细信息

关键词： collective filled dragon

High resolution sequence stratigraphy of the Mishrif Formation(Cenomanian-Early Turonian)at zubair oilfield(al-rafdhiah dome),southern Iraq

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Petroleum Research 2024年第1期9卷 61-71页

作者： Aymen A.Lazim Maher J.Ismail Maher M.Mahdi Geoscience Department Zubair Field Operation DivisionBasra Oil CompanyIraq Basrah Oil Company WQ1 FODBasrahIraq University of Basrah College of ScienceGeology Dept.BasrahIraq

The Mishrif Formation(Cenomanian-E Turonian)is one of the most important geological formations in the Middle East and Iraq because it contains enormous petroleum accumulations.It is considered to be the first reservoir in the region,and is still being studied because of its economic significance.The carbonate of the Mishrif Formation derives from a variety of depositional settings,including mid-ramp,shoal,lagoon,and intertidal.The five main microfacies discussed in this paper are wackestone,packstone,grainstone,floatstone,and bindstone.The most frequent fossilised components found in the Mishrif Formation are rudists,benthic foraminifera,echinoderms,burrows molluscs,and algae.According to the microfacies and analysed wireline log data,the sequence stratigraphy of the studied formation is composed of two regression cycles.Five parasequences of transgressive-regressive cycles make up the depositional sequence of the Mishrif Formation.The standard depositional environments seem to demonstrate a gradual regression,beginning with a short period of the outer ramp,then a steady period of the mid-ramp,and ending in the intertidal environment.Additionally,the study recorded two regional maximum flooding surfaces:K-135 and K-140.The former is present in the lowermost part of the formation,while the other lies in the middle.This study shows a close relationship between facies(environments)and hydrocarbon accumulation.The increased accumulation focuses on the lower part of the studied formation,and seems to be lower in the upper part of the formation as a result of changes in the environment of deposition.

关键词： Mishrif formation Cenomanian Sequence stratigraphy Zubair oilfield Iraq

Use of Unconventional Aggregates in Hot Mix Asphalt Concrete

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Journal of Civil Engineering and Architecture 2024年第1期18卷 30-37页

作者： Viktors Haritonovs dept.of Roads and Bridges Riga Technical UniversityRigaLatvia

The study investigates use of dolomite sand waste as filler or/and sand material plus BOF steel slag as fine and coarse aggregate for design of high performance asphalt concrete.Both environmental and economic factors contribute to the growing need for the use of these materials in asphalt concrete pavements.This is particularly important for Latvia,where local crushed dolomite and sandstone does not fulfill the requirements for mineral aggregate in high and medium intensity asphalt pavements roads.Annually 100 to 200 thousand tons of steel slag aggregates are produced in Latvia.However,it has not been used extensively in asphalt pavement despite its high performance characteristics.Dolomite sand waste,which is byproduct of crushed dolomite production,is another widely available polydisperse by-product in Latvia.Its quantity has reached a million of tons and is rapidly increasing.This huge quantity of technological waste needs to be recycled with maximum efficiency.Various combinations of steel slag,dolomite sand waste and conventional aggregates were used to develop AC 11 asphalt concrete mixtures.The mix properties tests include resistance to permanent deformations(wheel tracking test,dynamic creep test)and fatigue resistance.Laboratory test results showed that asphalt concrete mixtures containing steel slag and local limestone in coarse portion and dolomite sand waste in sand and filler portions had high resistance to plastic deformations and good resistance to fatigue failure.

关键词： Steel slag dolomite sand waste permanent deformation creep test fatigue

Ce^(4+)-Induced Apoptosis of Taxus cuspidata Cells in Suspension Culture

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Journal of Rare Earths 2002年第2期20卷 139-144页

作者：葛志强元英进王艳东马振毅胡宗定 dept. of biochem. Eng. Sch. of Chem. Eng. and Technol. Tianjin Univ. Tianjin 300072 China

The standard detection hallmarks of apoptosis of Taxus cuspidata cells in suspension culture with Ce 4+ were studied. The condensation and margination of chromatin were observed under the electron microscopy. DNA fragmentation ranged 'DNA ladder' on agarose gel electrophoresis. TdT mediated dUTP nick end labeling (TUNEL) analysis of the cells reveals that the nuclear DNA strand breaks can be identified by labeling free 3′ OH termini. These results suggest that Ce 4+ can induce apoptosis of Taxus cuspidata cells and also indicate that there is a certain relationship between apoptosis and secondary metabolite product Taxol.

关键词： rare earths cerium apoptosis Taxus cuspidata cell suspension culture

Continuous-wave operation of 1550 nm low-threshold triple-lattice photonic-crystal surface-emitting lasers

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Light(Science & Applications) 2024年第3期13卷 446-453页

作者： Ziye Wang Xia Liu Pinyao Wang Huanyu Lu Bo Meng Wei Zhang Lijie Wang Yanjing Wang Cunzhu Tong State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Central Research Institute Planning dept 2012 LabsHuawei Technologies Company Ltd.Shenzhen 518129China

Benefitting from narrow beam divergence,photonic crystal surface-emitting lasers are expected to play an essential role in the ever-growing fields of optical communication and light detection and ranging.Lasers operating with 1.55μm wavelengths have attracted particular attention due to their minimum fiber loss and high eye-safe threshold.However,high interband absorption significantly decreases their performance at this 1.55μm wavelength.Therefore,stronger optical feedback is needed to reduce their threshold and thus improve the output power.Toward this goal,photonic-crystal resonators with deep holes and high dielectric contrast are often used.Nevertheless,the relevant techniques for high-contrast photonic crystals inevitably complicate fabrication and reduce the final yield.In this paper,we demonstrate the first continuous-wave operation of 1.55μm photonic-crystal surface-emitting lasers by using a‘triple-lattice photonic-crystal resonator’,which superimposes three lattice point groups to increase the strength of in-plane optical feedback.Using this geometry,the in-plane 180°coupling can be enhanced threefold compared to the normal single-lattice structure.Detailed theoretical and experimental investigations demonstrate the much lower threshold current density of this structure compared to‘single-lattice’and‘double-lattice’photonic-crystal resonators,verifying our design principles.Our findings provide a new strategy for photonic crystal laser miniaturization,which is crucial for realizing their use in future high-speed applications.

关键词： resonator crystal lattice